请输入您要查询的英文单词:

 

单词 velamen
释义

Definition of velamen in English:

velamen

nounPlural velamina vɪˈleɪmənvəˈlāmən
Botany
  • An outer layer of empty cells in the aerial roots of epiphytic orchids and aroids.

    Example sentencesExamples
    • Orchid roots are covered with a special tissue called velamen occurring only in a very few non-orchid plant families.
    • The role of the velamen is to absorb moisture from the ambient atmosphere, and, may be, to protect from cold or heat.
    • Over watering turns the velamen brown and mushy and the roots lose their ability to absorb water.
    • When water is in short supply, the dry velamen restricts water loss from the roots.
    • While dry, the velamen may provide a barrier to water loss via transpiration from the wet, internal cells of the root.

Origin

Late 19th century: from Latin, from velare 'to cover'.

 
 

Definition of velamen in US English:

velamen

nounvəˈlāmən
Botany
  • An outer layer of empty cells in the aerial roots of epiphytic orchids and aroids.

    Example sentencesExamples
    • When water is in short supply, the dry velamen restricts water loss from the roots.
    • The role of the velamen is to absorb moisture from the ambient atmosphere, and, may be, to protect from cold or heat.
    • Over watering turns the velamen brown and mushy and the roots lose their ability to absorb water.
    • While dry, the velamen may provide a barrier to water loss via transpiration from the wet, internal cells of the root.
    • Orchid roots are covered with a special tissue called velamen occurring only in a very few non-orchid plant families.

Origin

Late 19th century: from Latin, from velare ‘to cover’.

 
 
随便看

 

英语词典包含464360条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2024/11/11 7:26:23